In a wireless local area network (WLAN), an excessive number of stations (STAs) in a network or a node may increase a probability of collisions occurring between the STAs. To solve such an issue, a method of using a slotted channel access may be proposed. In the method, an access point (AP) may divide a channel access interval into a slot having a predetermined length, and allocate, to the slot, a point in time at which the STA accesses the channel. The AP may notify the STA of a location and an interval of the allocated slot using a beacon or a broadcast frame and thus, the STA may perform a data exchange in the allocated slot by listening to the beacon. Allocating a slot may allow a predetermined STA or a predetermined STA group exclusive access to a channel. In this instance, a disallowed STA may not access the channel and thus, a number of STAs simultaneously accessing the channel may be reduced. However, when an STA which does not listen to a beacon or a predetermined STA of a basic service set (BSS) adjacent to an overlapping basic service set (OBSS) accesses the channel in the allocated slot, competition may occur with an STA already allocated to the slot, because in the allocated slot, the STA may access the channel using a distributed coordination function (DCF) of a carrier sense multiple access with collision avoidance (CSMA/CA) scheme, in lieu of a time division multiple access (TDMA) scheme. In particular, when the allocated slot corresponds to an uplink (UL) for transmitting data to the AP, a back-off occurring due to a collision between the STAs may increase in power consumption. To ensure that the STA allocated based on the DCF accesses the channel in view of priority, the AP may need to additionally protect the slot allocated to the STA. The STA may not make a full use of of the allocated slot being protected with a method of, for example, acquiring a network allocation vector (NAV) by a request to send/clear to send (RTS/CTS) exchange, restricting the channel access using the beacon by the AP, or using a predetermined frame for the protection. In this instance, another STA may be allowed to access the channel by releasing the NAV.